What is quantum computing? – TechTarget
Quantum computing is an area of study focused on the development of computer based technologies centered around the principles ofquantum theory. Quantum theory explains the nature and behavior of energy and matter on thequantum(atomic and subatomic) level. Quantum computing uses a combination ofbitsto perform specific computational tasks. All at a much higher efficiency than their classical counterparts. Development ofquantum computersmark a leap forward in computing capability, with massive performance gains for specific use cases. For example quantum computing excels at like simulations.
The quantum computer gains much of its processing power through the ability for bits to be in multiple states at one time. They can perform tasks using a combination of 1s, 0s and both a 1 and 0 simultaneously. Current research centers in quantum computing include MIT, IBM, Oxford University, and the Los Alamos National Laboratory. In addition, developers have begun gaining access toquantum computers through cloud services.
Quantum computing began with finding its essential elements. In 1981, Paul Benioff at Argonne National Labs came up with the idea of a computer that operated with quantum mechanical principles. It is generally accepted that David Deutsch of Oxford University provided the critical idea behind quantum computing research. In 1984, he began to wonder about the possibility of designing a computer that was based exclusively on quantum rules, publishing a breakthrough paper a few months later.
Quantum Theory
Quantum theory's development began in 1900 with a presentation by Max Planck. The presentation was to the German Physical Society, in which Planck introduced the idea that energy and matter exists in individual units. Further developments by a number of scientists over the following thirty years led to the modern understanding of quantum theory.
Quantum Theory
Quantum theory's development began in 1900 with a presentation by Max Planck. The presentation was to the German Physical Society, in which Planck introduced the idea that energy and matter exists in individual units. Further developments by a number of scientists over the following thirty years led to the modern understanding of quantum theory.
The Essential Elements of Quantum Theory:
Further Developments of Quantum Theory
Niels Bohr proposed the Copenhagen interpretation of quantum theory. This theory asserts that a particle is whatever it is measured to be, but that it cannot be assumed to have specific properties, or even to exist, until it is measured. This relates to a principle called superposition. Superposition claims when we do not know what the state of a given object is, it is actually in all possible states simultaneously -- as long as we don't look to check.
To illustrate this theory, we can use the famous analogy of Schrodinger's Cat. First, we have a living cat and place it in a lead box. At this stage, there is no question that the cat is alive. Then throw in a vial of cyanide and seal the box. We do not know if the cat is alive or if it has broken the cyanide capsule and died. Since we do not know, the cat is both alive and dead, according to quantum law -- in a superposition of states. It is only when we break open the box and see what condition the cat is in that the superposition is lost, and the cat must be either alive or dead.
The principle that, in some way, one particle can exist in numerous states opens up profound implications for computing.
A Comparison of Classical and Quantum Computing
Classical computing relies on principles expressed by Boolean algebra; usually Operating with a 3 or 7-modelogic gateprinciple. Data must be processed in an exclusive binary state at any point in time; either 0 (off / false) or 1 (on / true). These values are binary digits, or bits. The millions of transistors and capacitors at the heart of computers can only be in one state at any point. In addition, there is still a limit as to how quickly these devices can be made to switch states. As we progress to smaller and faster circuits, we begin to reach the physical limits of materials and the threshold for classical laws of physics to apply.
The quantum computer operates with a two-mode logic gate:XORand a mode called QO1 (the ability to change 0 into a superposition of 0 and 1). In a quantum computer, a number of elemental particles such as electrons or photons can be used. Each particle is given a charge, or polarization, acting as a representation of 0 and/or 1. Each particle is called a quantum bit, or qubit. The nature and behavior of these particles form the basis of quantum computing and quantum supremacy. The two most relevant aspects of quantum physics are the principles of superposition andentanglement.
Superposition
Think of a qubit as an electron in a magnetic field. The electron's spin may be either in alignment with the field, which is known as aspin-upstate, or opposite to the field, which is known as aspin-downstate. Changing the electron's spin from one state to another is achieved by using a pulse of energy, such as from alaser. If only half a unit of laser energy is used, and the particle is isolated the particle from all external influences, the particle then enters a superposition of states. Behaving as if it were in both states simultaneously.
Each qubit utilized could take a superposition of both 0 and 1. Meaning, the number of computations a quantum computer could take is 2^n, where n is the number of qubits used. A quantum computer comprised of 500 qubits would have a potential to do 2^500 calculations in a single step. For reference, 2^500 is infinitely more atoms than there are in the known universe. These particles all interact with each other via quantum entanglement.
In comparison to classical, quantum computing counts as trueparallel processing. Classical computers today still only truly do one thing at a time. In classical computing, there are just two or more processors to constitute parallel processing.EntanglementParticles (like qubits) that have interacted at some point retain a type can be entangled with each other in pairs, in a process known ascorrelation. Knowing the spin state of one entangled particle - up or down -- gives away the spin of the other in the opposite direction. In addition, due to the superposition, the measured particle has no single spin direction before being measured. The spin state of the particle being measured is determined at the time of measurement and communicated to the correlated particle, which simultaneously assumes the opposite spin direction. The reason behind why is not yet explained.
Quantum entanglement allows qubits that are separated by large distances to interact with each other instantaneously (not limited to the speed of light). No matter how great the distance between the correlated particles, they will remain entangled as long as they are isolated.
Taken together, quantum superposition and entanglement create an enormously enhanced computing power. Where a 2-bit register in an ordinary computer can store only one of four binary configurations (00, 01, 10, or 11) at any given time, a 2-qubit register in a quantum computer can store all four numbers simultaneously. This is because each qubit represents two values. If more qubits are added, the increased capacity is expanded exponentially.
Quantum Programming
Quantum computing offers an ability to write programs in a completely new way. For example, a quantum computer could incorporate a programming sequence that would be along the lines of "take all the superpositions of all the prior computations." This would permit extremely fast ways of solving certain mathematical problems, such as factorization of large numbers.
The first quantum computing program appeared in 1994 by Peter Shor, who developed a quantum algorithm that could efficiently factorize large numbers.
The Problems - And Some Solutions
The benefits of quantum computing are promising, but there are huge obstacles to overcome still. Some problems with quantum computing are:
There are many problems to overcome, such as how to handle security and quantum cryptography. Long time quantum information storage has been a problem in the past too. However, breakthroughs in the last 15 years and in the recent past have made some form of quantum computing practical. There is still much debate as to whether this is less than a decade away or a hundred years into the future. However, the potential that this technology offers is attracting tremendous interest from both the government and the private sector. Military applications include the ability to break encryptions keys via brute force searches, while civilian applications range from DNA modeling to complex material science analysis.
See the rest here:
What is quantum computing? - TechTarget
- How a quantum computer can be used to actually steal your bitcoin in '9 minutes' - CoinDesk - April 19th, 2026 [April 19th, 2026]
- Quantum stocks on pace for a massive week after Nvidia debuts AI models to boost the tech - CNBC - April 19th, 2026 [April 19th, 2026]
- 3 Best Quantum Computing Stocks to Buy in April 2026, According to Analysts - TipRanks - April 19th, 2026 [April 19th, 2026]
- Why Quantum Computing Stock Was Blasting Higher This Week - Yahoo Finance - April 19th, 2026 [April 19th, 2026]
- Quantum-informed AI improves long-term turbulence forecasts while using far less memory - Phys.org - April 19th, 2026 [April 19th, 2026]
- Quantum Frontiers: Stony Brook Researchers Chart the Future of Technology - SBU News - April 19th, 2026 [April 19th, 2026]
- Quantum Jamming Explores the Truly Fundamental Principles of Nature - Quanta Magazine - April 19th, 2026 [April 19th, 2026]
- University of Illinois Renews Quantum Tech Partnership With IBM - govtech.com - April 19th, 2026 [April 19th, 2026]
- Oxford scientists achieve quantum gate teleportation between two quantum supercomputers - The Brighter Side of News - April 19th, 2026 [April 19th, 2026]
- Ferguson invests in Snohomish County to make it the Quantum Valley of the West - Lynnwood Times - April 19th, 2026 [April 19th, 2026]
- Alice & Bob Surpasses Hiring Targets Ahead of Schedule as Quantum Workforce Grows - HPCwire - April 19th, 2026 [April 19th, 2026]
- How IonQ Became the Most Exciting Name in Quantum Computing This Week - inc.com - April 19th, 2026 [April 19th, 2026]
- How a quantum computer can be used to actually steal your bitcoin in '9 minutes' - Cryptonews.net - April 19th, 2026 [April 19th, 2026]
- India built a fully indigenous quantum computer in just four months. But what exactly can it do, and does it actually stand up against what the US,... - April 19th, 2026 [April 19th, 2026]
- Bitcoin miners are dealing with this triple-threat. Im a seven worried, says mining CEO - dlnews.com - April 19th, 2026 [April 19th, 2026]
- The Korea Quantum Trade: Why Seoul Produced the Biggest Stock Moves on NVIDIA's Ising Launch - The Quantum Insider - April 19th, 2026 [April 19th, 2026]
- 3 Screaming Buys for the Upcoming AI-Quantum Supercycle - The Motley Fool - April 19th, 2026 [April 19th, 2026]
- Satoshi Nakamoto is one of the richest people in the world, but a proposed update could lock his Bitcoin away forever - dlnews.com - April 19th, 2026 [April 19th, 2026]
- A $2M quantum prize went to cancer-treatment research on IBM - Stock Titan - April 19th, 2026 [April 19th, 2026]
- Recent advances push Big Tech closer to the Q-Day danger zone - Ars Technica - April 19th, 2026 [April 19th, 2026]
- NVIDIA Launches Ising, the Worlds First Open AI Models to Accelerate the Path to Useful Quantum Computers - NVIDIA Newsroom - April 17th, 2026 [April 17th, 2026]
- Quantum computing stocks are back on the rise. Heres why IONQ, QBTS, RGTI, and QUBT are up - Fast Company - April 17th, 2026 [April 17th, 2026]
- How IBM Quantum is enabling healthcare and biology research - IBM - April 17th, 2026 [April 17th, 2026]
- Key quantum computing stock jumps 20% in a day, heres why - thestreet.com - April 17th, 2026 [April 17th, 2026]
- QuEras Yuval Boger on Quantum Timelines, Neutral-Atom Systems, and the Hybrid Future - MeriTalk - April 17th, 2026 [April 17th, 2026]
- Why Quantum Computing Stock Was Blasting Higher This Week - The Motley Fool - April 17th, 2026 [April 17th, 2026]
- Quantum Computing Advanced Packaging Market to 2035 Driven by Scaling Qubit Counts in Processors - IndexBox - April 17th, 2026 [April 17th, 2026]
- Quantum Fourier transform reaches 52 qubits, shattering the previous 27-qubit record - Phys.org - April 17th, 2026 [April 17th, 2026]
- Israel Is Winning the Quantum Race. It May Not Finish It - The Times of Israel - April 17th, 2026 [April 17th, 2026]
- University of Illinois and IBM renew quantum technology partnership at new Chicago headquarters - Chicago Tribune - April 17th, 2026 [April 17th, 2026]
- Quantum Computing's Crypto Threat Is Getting Realand Investors Are Piling In - MarketBeat - April 17th, 2026 [April 17th, 2026]
- Pulsar Helium: "Blue Gold" And Its Role In Quantum Computing (OTCMKTS:PSRHF) - Seeking Alpha - April 17th, 2026 [April 17th, 2026]
- Analysts Are Bullish on These 3 Quantum Computing Stocks Including One Youve Never Heard Of - Yahoo Finance - April 17th, 2026 [April 17th, 2026]
- Quantum photonics roadmap how Xanadu and PsiQuantum are looking to transfer qubits through beams of light - Tom's Hardware - April 17th, 2026 [April 17th, 2026]
- Quantum Computing Stocks Are Surging. New Models From Nvidia Are Helping Drive the Rally. - Investopedia - April 17th, 2026 [April 17th, 2026]
- IBM and University of Illinois Extend Discovery Accelerator Institute to Link Quantum and HPC Systems - HPCwire - April 17th, 2026 [April 17th, 2026]
- 15 months after crippling quantum computing stocks, Nvidia has sent the industry back into the stratosphere - Sherwood News - April 17th, 2026 [April 17th, 2026]
- VPNs Will Be Useless On A Quantum Internet Your Location Can Always Be Known - IFLScience - April 17th, 2026 [April 17th, 2026]
- UMD ARLIS Breaks Ground on $65M Facility to Support Applied Quantum and Intelligence Missions - HPCwire - April 17th, 2026 [April 17th, 2026]
- Moth Bets Quantum Computing Will Reach Consumers by Next World Quantum Day - The Quantum Insider - April 17th, 2026 [April 17th, 2026]
- BTQ Technologies Advances Quantum Reliability at Scale with First General Theory of Error Correction for Permutation-Invariant Codes - PR Newswire - April 17th, 2026 [April 17th, 2026]
- Famed investor Andrew Left says Nvidia has already crowned the big quantum stock winner - AOL.com - April 17th, 2026 [April 17th, 2026]
- Should You Buy Sell or Hold IonQ at $42 Is the Quantum Rally Back? - 24/7 Wall St. - April 17th, 2026 [April 17th, 2026]
- Quantum Clock Is Ticking: Colton Dillion on Building the Worldwide Quantum Computer Before Crypto Breaks - CCN.com - April 17th, 2026 [April 17th, 2026]
- IonQ, Nvidia Make Strides on World Quantum Day. Whats Lifting the Stocks. - Barron's - April 14th, 2026 [April 14th, 2026]
- Prediction: This Will Be Rigetti Computing's Stock Price in 1 Year - The Motley Fool - April 14th, 2026 [April 14th, 2026]
- D-Wave CEO Brings Commercial Quantum Computing to the Center of Global Economic and Technology Discussions at Semafor World Economy and QED-C Quantum... - April 14th, 2026 [April 14th, 2026]
- Quantum Computing vs Classical Computing Whats the Real Difference - The Quantum Insider - April 14th, 2026 [April 14th, 2026]
- How Columbus is leading the way on World Quantum Day - The Columbus Dispatch - April 14th, 2026 [April 14th, 2026]
- What Quantum Technology is and Why it Matters - The Quantum Insider - April 14th, 2026 [April 14th, 2026]
- Global Quantum Computing Market to Double by 2028, Reaching $3 Billion in Revenue, QED-C State of the Global Quantum Industry 2026 Report Finds - The... - April 14th, 2026 [April 14th, 2026]
- IQM Introduces AI-Based Calibration for Scalable Quantum Systems - The Quantum Insider - April 14th, 2026 [April 14th, 2026]
- France bets 500 million that quantum computing is the tech race Europe can finally win - The Next Web - April 14th, 2026 [April 14th, 2026]
- Bull and Equal1 Partner to Accelerate Hybrid Quantum-HPC Integration in Europe - HPCwire - April 14th, 2026 [April 14th, 2026]
- Nvidia slaps forehead: AI, thats what quantum needs! - theregister.com - April 14th, 2026 [April 14th, 2026]
- Today is World Quantum Day. Heres why it matters more than you think - Fast Company - April 14th, 2026 [April 14th, 2026]
- Bull and Equal1 Partner on Hybrid Quantum and HPC Integration - The Quantum Insider - April 14th, 2026 [April 14th, 2026]
- Intersection of humanities and quantum physics discussed during URIs World Quantum Day - The University of Rhode Island - April 14th, 2026 [April 14th, 2026]
- Rigetti Computing vs. IonQ: Diverging Trends in Quarterly Revenue - The Motley Fool - April 14th, 2026 [April 14th, 2026]
- Curious about quantum? Check out training options from ISC2, IBM, AWS and more - Network World - April 14th, 2026 [April 14th, 2026]
- Quantum computing is a once-in-a-lifetime opportunity for Canada. Here's how we can grow the industry at home - Financial Post - April 14th, 2026 [April 14th, 2026]
- Quantum-HPC convergence moves from theory to mission - SiliconANGLE - April 14th, 2026 [April 14th, 2026]
- Quantum Computing (NASDAQ:QUBT) Trading Up 11% - Here's Why - MarketBeat - April 14th, 2026 [April 14th, 2026]
- Quantum-Day Reality Check: Debunking the Quantum Threat to Crypto - CCN.com - April 14th, 2026 [April 14th, 2026]
- Gauge theory could give quantum error correction a boost - Physics World - April 14th, 2026 [April 14th, 2026]
- Guest Post: The Global Quantum Race is Here And Politicians Must Keep Up - The Quantum Insider - April 14th, 2026 [April 14th, 2026]
- IonQ, Rigetti, D-Wave and Nvidia Rise on World Quantum Day. What's Lifting the Stocks. - Moomoo - April 14th, 2026 [April 14th, 2026]
- IonQ Soars 18%, D-Wave Climbs 15%, Rigetti Gains 12%: Is the Quantum Super-Cycle Back in Full Force? - 24/7 Wall St. - April 14th, 2026 [April 14th, 2026]
- IQM Advances AI-Driven Agentic Calibration, Opening Quantum Computing to the Enterprise With NVIDIA Ising - PA Media - April 14th, 2026 [April 14th, 2026]
- The Best Quantum Computing Stocks to Buy Today - The Motley Fool - April 12th, 2026 [April 12th, 2026]
- Quantum Computing Is Beginning to Take Shape Here Are Three Recent Breakthroughs - Discover Magazine - April 12th, 2026 [April 12th, 2026]
- How Sensitive Are The Computers Of The Future? - Eurasia Review - April 12th, 2026 [April 12th, 2026]
- The Quantum Computing ETF That Could Be Bigger Than AI, and 2 Tech Funds Riding the Same Wave - 24/7 Wall St. - April 12th, 2026 [April 12th, 2026]
- Quantum Computing Threat to Bitcoin: Google Warns of Accelerated Timeline - News and Statistics - IndexBox - April 12th, 2026 [April 12th, 2026]
- Is Rigetti Computing's New 2-Qubit Gate Fidelity Record a Reason to Buy the Stock? - Yahoo Finance - April 12th, 2026 [April 12th, 2026]
- Quantum XChanges Eddy Zervigon on Q-Day, PQC Readiness, and How Federal CIOs Can Start the Migration Now - MeriTalk - April 12th, 2026 [April 12th, 2026]
- Guest Post: The UK's Quantum Ambitions Will Fail Without The Components to Make Them Real - The Quantum Insider - April 12th, 2026 [April 12th, 2026]
- The Quantum Computing ETF That Could Be Bigger Than AI, and 2 Tech Funds Riding the Same Wave - AOL.com - April 12th, 2026 [April 12th, 2026]
- Quantum threat looms far beyond Bitcoin, says Grayscale - thestreet.com - April 12th, 2026 [April 12th, 2026]
- How Should We Prepare for the Looming Quantum Encryption Apocalypse? - Gizmodo - April 12th, 2026 [April 12th, 2026]